Contemporary clinical management of isolated high-grade prostatic intraepithelial neoplasia

A Tale of Two Cancers: A Current Concise Overview of Breast and Prostate Cancer

Simple Summary

Breast and prostate cancers are serious public health issues that create considerable burden to both people and healthcare systems worldwide. Cancer is a heterogeneous disease influenced by numerous components, and its diverse intricate pathology challenges disease prevention, diagnosis, treatment, and survival. Although recent statistics suggest improvements in cancer diagnosis and treatment, many challenges remain before cancers are curable. This review presents relevant summarized information related to breast and prostate cancer.

Abstract

Cancer is a global issue, and it is expected to have a major impact on our continuing global health crisis. As populations age, we see an increased incidence in cancer rates, but considerable variation is observed in survival rates across different geographical regions and cancer types. Both breast and prostate cancer are leading causes of morbidity and mortality worldwide. Although cancer statistics indicate improvements in some areas of breast and prostate cancer prevention, diagnosis, and treatment, such statistics clearly convey the need for improvements in our understanding of the disease, risk factors, and interventions to improve life span and quality of life for all patients, and hopefully to effect a cure for people living in developed and developing countries. This concise review compiles the current information on statistics, pathophysiology, risk factors, and treatments associated with breast and prostate cancer.

Inflammation in prostate cancer progression and therapeutic targeting

Chronic inflammation contributes to the onset and progression of human cancer, via modifications in the tumor microenvironment by remodeling the extracellular matrix (ECM) and initiating epithelial mesenchymal transition (EMT). At the biological level, chronically inflamed cells release cytokines that are functionally dictating a constitutively active stroma, promoting tumor growth and metastasis. In prostate cancer, inflammation correlates with increased development of “risk factor” lesions or proliferative inflammatory atrophy (PIA). Chronic inflammation in benign prostate biopsy specimens can be associated with high-grade prostate tumors in adjacent areas. In this article, we discuss the current understanding of the incidence of inflammation in prostate cancer progression and the significance of the process in therapeutic targeting of specific inflammatory signaling pathways and critical effectors during tumor progression. Further understanding of the process of chronic inflammation in prostate tumor progression to metastasis will enable development and optimization of novel therapeutic modalities for the treatment of high-risk patients with advanced disease.

Inverted (hobnail) high-grade prostatic intraepithelial neoplasia and invasive inverted pattern

High-grade prostatic intraepithelial neoplasia (HGPIN) is considered to be an important precursor for prostatic adenocarcinoma. The present study aimed to investigate the histological features of the uncommon inverted (hobnail) pattern of HGPIN in transrectal ultrasonographic (TRUS) prostatic needle biopsies from 13 cases. These 13 diagnosed cases of inverted HGPIN were identified out of a total of 2,034 TRUS biopsies (0.63%), obtained from patients suspected to have prostate cancer. The hobnail pattern is comprised of secretory cell nuclei, which are histologically localized at the luminal surface of the prostate gland, rather than the periphery, and exhibit reverse polarity. Histological examinations were performed and the results demonstrated that 5 of the 13 cases exhibited pure inverted histology, while HGPIN was observed to be histologically associated with other patterns in the remaining 8 patients. In addition, an association with adenocarcinoma was identified in 7 of the 13 cases. All 7 carcinomas accompanied by inverted HGPIN were conventional acinar adenocarcinoma cases; of note, for these 7 cases, the Gleason score was 7 for each. One acinar adenocarcinoma case accompanying inverted HGPIN demonstrated hobnail characteristics in large areas of the invasive component. It was observed that nuclei were proliferated in the invasive cribriform glands, which was comparable to that of inverted HGPIN, and were located on the cytoplasmic luminal surface; a similar morphology was also observed in individual glands. In conclusion, the results of the present study suggested that the hobnail HGPIN pattern may be of diagnostic importance due to its high association with adenocarcinoma and the high Gleason scores in the accompanying carcinomas.

Current significance of the finding of high grade prostatic intraepithelial neoplasia in the prostate biopsy

INTRODUCTION

High grade prostatic intraepithelial neoplasia (HGPIN) is regarded as a precursor of prostate cancer (PC). However, its relationship to cancer has changed throughout the literature, being currently poorly defined and remains controversial for urologists in their clinical practice. Because of his frequency and the impact on patient outcomes that the lack of consensus clinical attitude could carry out, it seems advisable to review the understanding of this disease.

OBJECTIVE

The aim of this literature review is to summarize the main features of this entity (histopathology, molecular, epidemiological) and evaluate their relationship with prostate adenocarcinoma, explaining the variation of incidence seen in the literature and the clinical significance of their finding.

MATERIAL AND METHODS

Review of the literature, based on the research and analysis of publications found in Pubmed with the words "prostate" and "intraepithelial neoplasms".

RESULTS

The HGPIN detection rate has increased to the extent that it has increased the number of punctures in prostate biopsies. With the current biopsy schemes (10-12 punctures), the detection rate of PC in repeat biopsies is similar in patients with and without isolated HGPIN. However, HGPIN multifocality predicts increased risk of PC detection in repeat biopsy.

CONCLUSION

HGPIN detection is common with current biopsy schemes. Its genetic relationship with PC is clear and its multifocality is the most important predictor factor of PC.

Preneoplasia in the prostate gland with emphasis on high grade prostatic intraepithelial neoplasia

There are a variety of morphological patterns and processes that have been implicated in the pathogenesis of prostate cancer. Prostatic intraepithelial neoplasia (PIN), inflammation with or without atrophy, and adenosis (atypical adenomatous hyperplasia) have all been given candidate status as precursor lesions of prostatic adenocarcinoma. Based on decades of research, high grade prostatic intraepithelial neoplasia (HPIN), a proliferative lesion of prostatic secretory cells, has emerged as the most likely morphological pre-invasive lesion involved in the evolution of many but not all prostatic adenocarcinomas. In this manuscript, we briefly discuss other proposed precursors of prostatic adenocarcinoma and then focus on the history, diagnostic criteria and morphology of HPIN. The incidence of HPIN and its relationship to prostate cancer is reviewed. The differential diagnosis of large glandular patterns in the prostate is discussed in depth. Finally, we summarise the recent clinicopathological studies evaluating the clinical significance of HPIN and discuss follow-up strategies in men diagnosed with HPIN.

Precursors of prostate cancer

High-grade prostatic intraepithelial neoplasia (PIN) is the only accepted precursor of prostatic adenocarcinoma, according to numerous studies of animal models and man; other proposed precursors include atrophy and malignancy-associated changes (with no morphologic changes). PIN is characterized by progressive abnormalities of phenotype and genotype that are intermediate between benign prostatic epithelium and cancer, indicating impairment of cell differentiation and regulatory control with advancing stages of prostatic carcinogenesis. The only method of detection of PIN is biopsy because it does not significantly elevate serum prostate-specific antigen concentration and cannot be detected by ultrasonography. The mean incidence of PIN in biopsies is 9% (range, 4%-16%), representing about 115,000 new cases of isolated PIN diagnosed each year in the United States. The clinical importance of PIN is its high predictive value as a marker for adenocarcinoma, and its identification warrants repeat biopsy for concurrent or subsequent carcinoma, especially when multifocal or observed in association with atypical small acinar proliferation (ASAP). Carcinoma develops in most patients with PIN within 10 years. Androgen deprivation therapy and radiation therapy decrease the prevalence and extent of PIN, suggesting that these forms of treatment may play a role in prevention of subsequent cancer. Multiple clinical trials to date of men with PIN have had modest success in delaying or preventing subsequent cancer.

In situ and intraductal epithelial proliferations of prostate: definitions and treatment implications. Part 1: Prostatic intraepithelial neoplasia

What's known on the subject? and What does the study add? In the era of extended biopsy sampling of the prostate, multifocal high-grade prostatic intraepithelial neoplasia (HGPIN) is associated with a significantly higher rate of cancer diagnosis than unifocal HGPIN or a benign diagnosis. In addition, the cancers that are subsequently diagnosed in men with HGPIN on their initial biopsy tend to be smaller, lower grade and more commonly organ-confined. This has led to a reappraisal of the need and timing of repeat biopsies. The present paper provides a series of recommendations on the optimal timing of repeat biopsies in men with HGPIN on biopsy, based on the current available evidence. This is the first of a two part series reviewing the nature and clinical significance of in situ cellular proliferations in the prostate gland. This first part examines prostatic intraepithelial neoplasia (PIN), while the second part in the next supplement discusses intraductal carcinoma and ductal adenocarcinoma of the prostate. PIN is a precursor lesion in the development of some forms of adenocarcinoma of the prostate. In the 1990 s, high-grade PIN (HGPIN) on biopsy was a significant predictor of carcinoma, but this was due to incomplete sampling with sextant biopsies. With more extensive sampling in the last decade, the likelihood of identifying cancer after a diagnosis of HGPIN is not significantly different from a benign diagnosis. In several recent studies, it is now recognised that multifocal HGPIN is a better predictor of cancer than unifocal HGPIN. Most cases of cancer will be detected in the vicinity of the HGPIN, but up to 40% of cancers will occur in different sextants. In assessing potential markers for carcinoma in men with HGPIN on biopsy, α-methylacyl coenzyme-A racemase (AMACR) has emerged as a promising diagnostic tool. HGPIN with strong staining for AMACR is associated with a higher rate of cancer detection in subsequent biopsies compared with AMACR-negative HGPIN. Also, AMACR positivity in HGPIN is more commonly seen adjacent to carcinoma, and this may provide guidance as to the site of future biopsies.

Opposing roles of ERα and ERβ in the genesis and progression of adenocarcinoma in the rat ventral prostate

BACKGROUND

Prostate cancer is a common malignancy in men and although hormone ablation therapy is effective, men develop hormone resistance. There is need for therapies applicable earlier, such as treatment of prostatic intraepithelial neoplasia (PIN). Estrogens besides androgens play a role in prostate cancer pathogenesis via two receptors ERα and ERβ and both receptors are thought to play different, opposing, roles with ERα having proliferative properties and ERβ having anti-proliferative properties. To differentiate between the roles both receptors play in prostate cancer an ERα and an ERβ agonist, ERA-45 and ERB-26, have been tested in a rodent model for prostate carcinogenesis.

METHODS

The influence of ERα on prostate cancer progression was studied in intact male rats treated with testosterone in combination with the ERα agonist, ERA-45 for either a long-term (20-week) period or a shorter term (6-week) period. The ERβ agonist was tested in the shorter term model in intact male rats treated with testosterone in combination with the ERα agonist, ERA-45, followed by administration of the ERβ agonist, ERB-26, during the last 2 weeks.

RESULTS

Treatment of rats with testosterone in combination with ERA-45 induced mild PIN lesions at 6 weeks and severe precancerous PIN lesions at 20 weeks. The ERβ agonist prevented the onset of PIN lesions at 6 weeks. Moreover, prostate epithelial cell apoptosis was increased and proliferation was decreased.

CONCLUSION

These findings confirm the opposing roles ERα and ERβ play in prostate carcinogenesis and suggest a therapeutic opportunity of ERβ for treating precancerous PIN lesions.

Diagnosis of isolated high-grade prostatic intra-epithelial neoplasia: proposal of a nomogram for the prediction of cancer detection at saturation re-biopsy

Study Type--Diagnostic (case series). Level of Evidence 4. What's known on the subject? And what does the study add? Multifocality, age, PSA values, and biopsy protocols regarding the predictive value of high grade PIN have been discussed extensively in the literature. Our study developed for the first time a predictive nomogram that could be helpful for patient counselling and to guide the urologist to perform rPBX after an initial diagnosis of isolated HGPIN.

OBJECTIVE

• To evaluate factors that may predict prostate cancer (PCa) detection after the initial diagnosis of high-grade prostatic intra-epithelial neoplasia (HGPIN) on prostate biopsy (PBx) with six to 24 random cores.

PATIENTS AND METHODS

• We retrospectively evaluated 262 patients submitted from 1998 to 2007 to prostate re-biopsy (rPBx) after an initial HGPIN diagnosis in tertiary academic centres. • HGPIN diagnosis was obtained on initial systematic PBx with six to 24 random cores. • All patients were re-biopsied with a 'saturation' rPBx with 20-26 cores, with a median time to rPBx of 12 months. • All slides were reviewed by expert uropathologists.

RESULTS

• Plurifocal HGPIN (pHGPIN) was found in 115 patients and monofocal HGPIN (mHGPIN) was found in 147 patients. • In total, 108 and 154 patients, respectively, were submitted to >12-core initial PBx and ≤12-core initial PBx. • Overall PCa detection at rPBx was 31.7%. PSA level (7.7 vs 6.6 ng/mL; P= 0.031) and age (68 vs 64 years; P= 0.001) were significantly higher in patients with PCa at rPBx. • PCa detection was significantly higher in patients with a ≤12-core initial PBx than in those with a >12-core initial PBx (37.6% vs 23.1%; P= 0.01), as well as in patients with pHGPIN than in those with mHGPIN (40% vs 25.1%; P= 0.013). • At multivariable analysis, PSA level (P= 0.041; hazards ratio, HR, 1.08), age (P < 0.001; HR, 1.09), pHGPIN (P= 0.031; HR, 1.97) and ≤12-core initial PBx (P= 0.012; HR, 1.95) were independent predictors of PCa detection. • A nomogram including these four variables achieved 72% accuracy for predicting PCa detection after an initial HGPIN diagnosis.

CONCLUSIONS

• PCa detection on saturation rPBx after an initial diagnosis of HGPIN is significantly higher in patients with a ≤12-core initial PBx than those with a >12-core initial PBx and in patients with pHGPIN than in those with mHGPIN. • We developed a simple prognostic tool for the prediction of PCa detection in patients with initial HGPIN diagnosis who were undergoing saturation rPBx.

Prostate cancer detection after a negative prostate biopsy: lessons learnt in the Cleveland Clinic experience

Urologists are often faced with the dilemma of managing patients with a negative initial prostate biopsy in whom clinical or pathological risk for prostate cancer still exists. Such real-life challenging scenarios might raise questions such as: Who should undergo further biopsies? What are the optimal predictors for prostate cancer on subsequent biopsies? What is the optimal biopsy protocol that should be used? When to stop the biopsy cascade? The last decade has witnessed numerous studies that have analyzed factors conferring a significant risk for cancer discovered on repeat biopsies. We and others have developed predictive models to aid decision-making regarding pursuing further biopsies. For decades, high-grade prostatic intraepithelial neoplasia has been considered a strong risk indicator for subsequent cancer. However, it has been recently shown that only through segmentation of this heterogeneous population does the real risk profile emerge. Biopsy templates underwent modification regarding the number and location of cores with emergence of the transrectal or brachytherapy grid transperineal saturation biopsy. However, the best biopsy protocol remains controversial. We have refined the initial biopsy template to a 14 core initial biopsy template that optimizes cancer detection, and have shown that transrectal saturation biopsy significantly improves cancer detection for repeat biopsy. Another concern is the overdiagnosis of clinically insignificant cancer on repeat biopsies, so we explored ways to limit this, and to deal with its ramifications. Through carrying out a Medline literature search, we critically evaluated pertinent articles together with emphasis of our own journey in this arena to assist in the decision-making process for repeat biopsy population.

Premalignant and malignant prostate lesions: pathologic review

BACKGROUND

High-grade prostatic intraepithelial neoplasia (HGPIN) is currently the only recognized premalignant lesion of prostatic carcinoma.

METHODS

This review article discusses HGPIN, its link to prostatic adenocarcinoma, and the significance of its presence on needle biopsy. The criteria and clinical impact of the diagnosis of atypical small acinar proliferation on needle biopsy are reviewed. Certain subtypes of prostate cancer that are not associated with HGPIN are of clinical relevance, and the unique clinicopathologic features of these subtypes are discussed. Histologic variants of prostatic adenocarcinoma with distinct cell types are also described.

RESULTS

HGPIN is the only known pathologic factor currently available to distinguish which patients may be at risk for detecting carcinoma on repeat biopsy. Histologic variants are recognized due to the inference of a particular Gleason grade pattern associated with the cell type, hence affecting prognosis. Typically, pure forms of these histologic variants are associated with worse prognosis due to the associated high Gleason grades.

CONCLUSIONS

HGPIN has a strong association with acinar-type prostatic adenocarcinoma. HGPIN and acinar-type prostatic adenocarcinoma both show similar molecular alterations, providing further evidence of their association.

What is the pathologist saying? Interpretation of the prostate pathology report

Management of patients presenting with elevated serum prostate-specific antigen levels, or those with previously diagnosed prostate carcinoma, is very much dependent on the pathology report on needle biopsy or radical prostatectomy specimens obtained from these patients. In contrast to a diagnosis of benignity or high-grade prostatic intraepithelial neoplasia, a diagnosis of atypia on needle core biopsy is usually an indication for a repeat biopsy; however, it is important to understand that atypia and other related terms are not specific diagnoses. The pathology report on different prostate specimens with a diagnosis of carcinoma usually includes the Gleason grade and extent of carcinoma among other morphological prognostic and predictive factors. Understanding the significance of these morphological factors and how they are evaluated and incorporated into the pathology report, as well as newer developments in this field, can assist urologists in the interpretation of the pathological findings and ultimately lead to better clinical care.

Precursor lesions to prostatic adenocarcinoma

High-grade prostatic intraepithelial neoplasia (PIN) is the one well-documented precursor to adenocarcinoma of the prostate. This review article defines both low- and high-grade PIN. Unusual variants of high-grade PIN are illustrated. Benign lesions that may be confused with high-grade PIN, including central zone histology, clear cell cribriform hyperplasia, and basal cell hyperplasia are described and illustrated. High-grade PIN is also differentiated from invasive acinar (usual) and ductal adenocarcinoma. The incidence of high-grade PIN, its relationship to carcinoma (including molecular findings), and risk of cancer on rebiopsy are covered in detail. Finally, intraductal carcinoma of the prostate, a controversial entity, is discussed and differentiated from high-grade PIN.

Prognostic significance of alpha-methylacyl-coA racemase among men with high grade prostatic intraepithelial neoplasia in prostate biopsies

PURPOSE

Serum prostate specific antigen screening has increased the number of prostate biopsies performed increasing the number of patients with high grade prostatic intraepithelial neoplasia. The criteria for re-biopsy are not standardized but may be refined by the identification of novel biomarkers demonstrating prognostic significance. Alpha-methylacyl-CoA racemase is a robust marker of prostate cancer and is expressed in a subset of high grade prostatic intraepithelial neoplasia. This study evaluates the prognostic significance of alpha-methylacyl-coA racemase positive high grade prostatic intraepithelial neoplasia glands in prostate biopsies.

MATERIALS AND METHODS

Immunohistochemical staining with alpha-methylacyl-coA racemase and p63 was examined in a selected group of 62 patients with a diagnosis of high grade prostatic intraepithelial neoplasia on initial prostate biopsy, of which on repeat biopsy 32 had no carcinoma and 30 had prostate cancer. There was no significant difference in age, number of cores sampled or prostate specific antigen history between the 2 outcome groups (ANOVA p >0.9). High grade prostatic intraepithelial neoplasia glands in each case were evaluated for alpha-methylacyl-coA racemase and p63.

RESULTS

Reactivity for alpha-methylacyl-coA racemase was found in 27 of the 62 cases examined. Fisher's exact analysis revealed that patients with at least 1 alpha-methylacyl-coA racemase positive high grade prostatic intraepithelial neoplasia gland were 5.2 times more likely to have a subsequent diagnosis of prostate cancer on repeat biopsy than those without any alpha-methylacyl-coA racemase positive high grade prostatic intraepithelial neoplasia glands (p = 0.0044). No correlation was found between alpha-methylacyl-coA racemase positivity and any other clinical variable.

CONCLUSIONS

This is the first study to our knowledge to illustrate that alpha-methylacyl-coA racemase reactivity in high grade prostatic intraepithelial neoplasia may be useful to refine re-biopsy criteria and assist in clinical management decisions.